TITLE:
Pollution Characteristics of PM2.5 during a Typical Haze Episode in Xiamen, China
AUTHORS:
Fuwang Zhang, Jinsheng Chen, Tianxue Qiu, Liqian Yin, Xiaoqiu Chen, Jianshuan Yu
KEYWORDS:
Fine Particles; Haze; Water Soluble Inorganic Ions; Organic Carbon; Elemental Carbon; Elements; Light Extinction Coefficients; Xiamen
JOURNAL NAME:
Atmospheric and Climate Sciences,
Vol.3 No.4,
August
26,
2013
ABSTRACT: In this study, mass concentrations and chemical compositions of fine
particles, mass concentrations of coarse particles, light extinction, and
meteorological parameters in the atmosphere ofXiamenwere presented and analyzed to study the
chemical and optical characteristics of a typical haze episode from Dec 25,
2010 to Jan 1, 2011. The major chemical compositions of PM2.5, such
as water soluble inorganic ions (WSIIs), carbonaceous fractions (mainly composed
of organic carbon (OC) and elemental carbon (EC)), and elements were
determined. The results showed that with the typical haze episode process, the
concentrations of PM2.5 mass, WSIIs, OC, EC, and TE first increased and
then decreased. The average concentrations of PM2.5 mass in the
stages of Before Haze, During Haze, and After Haze were (88.80 ± 19.97),
(135.41 ± 36.20), and (96.35 ± 36.26) μg/m3, respectively. The corresponding
average concentrations of secondary organic carbon (SOC) were 6.72, 8.18, and 10.39
μg/m3, accounting for 46.5%, 27.0%, and 61.0% of OC, respectively. S42- , NO3-, and NH4+ were three major WSIIs species,
accounting for 31.4%, 26.0%, and 12.1% of total WSIIs. The major elements in PM2.5 were S, K, Fe, Zn, Pb, Ti, and Mn, covering 97.9% of the total elements, while the
percentage of the other ten elements was only 2.1%. The average value of light
extinction coefficients (bext)
was 371.0 ±147.1 Mm-1 during the typical haze episode. The
average percentage contributions to bext were 39.3% for organic mass, 19.9% for elemental carbon, 16.0% for ammonium sulfate, 13.0% for coarse
mass, and 11.8% for ammonium nitrate.